[sdiy] Keio TS201012

[Colin f]

In case anyone with a fondness for the filters in the miniKorg 700, 700S and
800DV decides to un-pot one of the Keio ICs and reverse engineer the
circuit, I'll save you the bother.
It's identical to the transistor buffered diode ring in the Korg 770
filters.
Only difference is that the 770 uses diode arrays instead of discrete
devices and doesn't have the cutoff range shifted by the octave selector
switch as on the 700(S).

Cheers,
Colin f